1. Field of the Invention
The invention relates to optimizing voice quality on networks that have voice over Internet Protocol communication devices. The optimization is based on taking and evaluating measurements of network performance pertaining to quality of the network connection.
2. Discussion of Related Art
The contents of U.S. Ser. No. 09/220,232 is incorporated herein by reference.
Support for end-to-end voice calls using the Internet as an alternative to traditional public switched telephone networks (PSTN) is conventional. Unlike the PSTN, which is circuit-switched, the Internet is packet-switched; communication on the Internet is accomplished by transmitting and receiving packets of data.
In addition to data, each packet contains an address to ensure that it is routed correctly. The format of these packets is defined by the Internet Protocol (IP). One type of allowable data is encoded, digitized voice. Thus, voice over IP (VOIP) is voice that is packetized as defined by IP, and communicated over the Internet or some other IP network for telephone-like communication.
Devices such as personal computers (PC) that are VoIP ready, wireless VoIP devices, intelligent phones that are VoIP ready, conferencing units, trunks that are VoIP ready, multi-media devices that are VoIP ready, and plain old telephone system (POTS) telephones connected to VoIP gateways may be VoIP end-points. Examples include Microsoft's NetMeeting, Nortel Networks's soft-client and IP based personal digital assistant (PDA) devices.
These end-points require real-time performance over IP networks. The end points are assumed to be distributed on one or more IP networks. Some devices will be on the same subnet on the same local area network (LAN) segment while others will be on different subnets, some of which could be at the end of a slow wide area network (WAN) connection. A problem arises, however, with respect to voice quality and other quality of service (QoS) parameters in an IP network.
Conventionally, bandwidth is reserved for particular IP end points by marking their packets with a priority level. However, about 90% of the networks today are not policy managed. With respect to the 10% that are policy managed, there are no solutions to the problems that exist when the bandwidth is insufficient to support a badly configured IP end-point.
Conventional software tools are available to help assess the performance of a network by measuring parameters of network performance. Such tools include a Ping tool, a Network trace tool and a packet loss measurement tool. These tools are standard with MICROSOFT WINDOWS product. They run from the command line (found under Start, Run on all WINDOWS operating systems). The commands are ‘ping IP_Address’ or ‘Trace IP_Address’. These tools are available with TCP/IP protocol stacks found under operating systems such as Linux/VxWorks, etc.
With the telecommunications networks transitioning from circuit switching to packet switching, phones, trunks and wireless devices are expected to be VoIP capable. Controlling these phones, trunks, and wireless devices to optimize media performance is desired.